[PATCH AUTOSEL 4.9 15/38] samples: bpf: Replace symbol compare of trace_event

[PATCH AUTOSEL 4.9 15/38] samples: bpf: Replace symbol compare of trace_event

[Sasha Levin]

From: "Daniel T. Lee" <danieltimlee@gmail.com>

[ Upstream commit bba1b2a890253528c45aa66cf856f289a215bfbc ]

Previously, when this sample is added, commit 1c47910ef8013
("samples/bpf: add perf_event+bpf example"), a symbol 'sys_read' and
'sys_write' has been used without no prefixes. But currently there are
no exact symbols with these under kallsyms and this leads to failure.

This commit changes exact compare to substring compare to keep compatible
with exact symbol or prefixed symbol.

Fixes: 1c47910ef8013 ("samples/bpf: add perf_event+bpf example")
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191205080114.19766-2-danieltimlee@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 samples/bpf/trace_event_user.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c
index 9a130d31ecf2..6fbb5eb9daf3 100644
--- a/samples/bpf/trace_event_user.c
+++ b/samples/bpf/trace_event_user.c
@@ -33,9 +33,9 @@ static void print_ksym(__u64 addr)
 		return;
 	sym = ksym_search(addr);
 	printf("%s;", sym->name);
-	if (!strcmp(sym->name, "sys_read"))
+	if (!strstr(sym->name, "sys_read"))
 		sys_read_seen = true;
-	else if (!strcmp(sym->name, "sys_write"))
+	else if (!strstr(sym->name, "sys_write"))
 		sys_write_seen = true;
 }
 
-- 
2.20.1

[PATCH AUTOSEL 4.9 33/38] net, sysctl: Fix compiler warning when only cBPF is present

[Sasha Levin]

From: Alexander Lobakin <alobakin@dlink.ru>

[ Upstream commit 1148f9adbe71415836a18a36c1b4ece999ab0973 ]

proc_dointvec_minmax_bpf_restricted() has been firstly introduced
in commit 2e4a30983b0f ("bpf: restrict access to core bpf sysctls")
under CONFIG_HAVE_EBPF_JIT. Then, this ifdef has been removed in
ede95a63b5e8 ("bpf: add bpf_jit_limit knob to restrict unpriv
allocations"), because a new sysctl, bpf_jit_limit, made use of it.
Finally, this parameter has become long instead of integer with
fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
and thus, a new proc_dolongvec_minmax_bpf_restricted() has been
added.

With this last change, we got back to that
proc_dointvec_minmax_bpf_restricted() is used only under
CONFIG_HAVE_EBPF_JIT, but the corresponding ifdef has not been
brought back.

So, in configurations like CONFIG_BPF_JIT=y && CONFIG_HAVE_EBPF_JIT=n
since v4.20 we have:

  CC      net/core/sysctl_net_core.o
net/core/sysctl_net_core.c:292:1: warning: ‘proc_dointvec_minmax_bpf_restricted’ defined but not used [-Wunused-function]
  292 | proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Suppress this by guarding it with CONFIG_HAVE_EBPF_JIT again.

Fixes: fdadd04931c2 ("bpf: fix bpf_jit_limit knob for PAGE_SIZE >= 64K")
Signed-off-by: Alexander Lobakin <alobakin@dlink.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191218091821.7080-1-alobakin@dlink.ru
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/sysctl_net_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index a6fc82704f0c..b4318c1b5b96 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -255,6 +255,7 @@ static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write,
 	return ret;
 }
 
+# ifdef CONFIG_HAVE_EBPF_JIT
 static int
 proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
 				    void __user *buffer, size_t *lenp,
@@ -265,6 +266,7 @@ proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
 
 	return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 }
+# endif /* CONFIG_HAVE_EBPF_JIT */
 
 static int
 proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write,
-- 
2.20.1